There is a growing trend in vehicle window assemblies to provide a one-piece unit, sometimes called a modular assembly, in which a frame or gasket of PVC is molded to the periphery of the window glass panel. These window assemblies may be installed by adhesively bonding a portion of the inner surface of the molded frame to the flange that defines the window opening in the vehicle, as opposed to mechanical attachment by screws or like fasteners. If the frame is particularly thick, or if the flange to which it is bonded is far removed from the outer surface of the frame, it may be difficult or nearly impossible to reach the bead to break it by conventional means. Access may also be made difficult if a molded lip on the outer surface of the frame covers the gap between the frame and the surrounding outer panels of the vehicle. This presents a problem if it is desired to remove and reinstall the window assembly, such as to repair a water leak.
There are disadvantages and drawbacks to known methods of removing adhesively installed windows which make them inapplicable to the type of window assembly described above. In the case of windshields that have only a window panel without a molded frame, it is practical to cut the adhesive bead from the outside of the vehicle, since it is easily accessible. This may be done by inserting a cutting wire through the gap between the edge of the window panel and the surrounding vehicle body panels, and then pulling it through from the inside of the vehicle to cut the bead. Generally, only a decorative molding, easily removed, blocks access to that gap. The pulling of the wire may be done by hand, and it is also known to use a winding device such as that shown in European Pat. No. 93-283-A2. The Rose U.S. Pat. No. 3,574,024, shows an adhesive bead which has a central heating wire therein, the ends of which are accessible from inside the vehicle. While the primary purpose for the wire is to carry an electric current to heat cure the adhesive bead, the ends of the wire may be grasped from inside the vehicle and stripped through half of the bead. However, outside access would still be necessary to cut the rest of the bead. That access is not likely to be available in a modular window assembly.
Known methods for removing a vehicle window assembly with access from the inside only also have drawbacks which make them inapplicable to modular window assemblies. The Ziegler U.S. Pat. No. 4,093,304, shows an adhesively bonded windshield in which a metal strip is crimped over the pinchweld flange that defines the window opening, under the entire extent of the adhesive bead. The bead can then be broken by stripping the metal strip from the flange. However, while only inside access is neccessary, it is necessary along the entire flange. In addition, the use of a separate structural piece which must be attached to the flange defeats the primary advantage of a modular window assembly, which is that it may be installed as a single unit in a single step. German patent application No. 669731-3.11.55 shows a window which, although not adhesively installed, does have a resilient peripheral gasket with a cutting wire embedded in a groove therein. The wire is accessible from the inside of the vehicle, and is stripped through the gasket, cutting it all the way through around its entire periphery. Such a method would be suitable only in a window assembly of this older type in which the sealing gasket is a separate unit that may be easily replaced. Cutting through such a large portion of a gasket molded to a window panel would either destroy it or damage it too greatly to reinstall successfully.